Simple catalysts that use atom-economical oxygen as the terminal oxidant to accomplish selective ortho-ortho, ortho-para, or para-para homo-couplings of phenols are described. In addition, chromium salen catalysts have been discovered as uniquely effective in the cross-coupling of different phenols with high chemo- and regioselectivity.

Hysteresis motors are self starting brushless synchronous motors which are being used widely due to their interesting features. Accurate modeling of the motors is crucial to successful investigating the dynamic performance of them. The hysteresis loops of the material used in the rotor and their influences on the parameters of the equivalent circuit are necessary to be taken into considerat...

The static synchronous compensator (STATCOM) is one type of FACTS devices which resembles in many respects a rotating synchronous condenser used for voltage control and reactive power compensation. The STATCOM can increase transmission capacity, damping low frequency oscillation, and improving voltage stability. This paper presents a control block diagram of STATCOM for the voltage stability im...

Rapid prototyping (RP) methods are used for production easily and quickly of a scale model of a physical part or assembly. Gas metal arc welding (GMAW) is a widespread process used for rapid prototyping of metallic parts. In this process, in order to obtain a desired welding geometry, it is very important to predict the weld bead geometry based on the input process parameters, which are voltage...

Installing subsurface tile drain systems in poorly drained claypan soils to improve corn ( L.) yields could potentially increase environmental phosphorus (P) loss through the tile drainage system. The objectives of the study were to quantify the average concentration and loss of ortho-P in tile drain water from a claypan soil and to determine whether managed subsurface drainage (MD) could reduc...

Nitration of N-acetyl anilides using a simple combination AgNO3 and K2S2O8 as stable nitro source an oxidant, respectively, was explored. The reaction practical to operate proceeded under considerably mild conditions (reflux in acetonitrile) within acceptable time (6 h). para-substituted gave only ortho-nitrated products moderate good yields (30–63% yields). ortho-, meta-, or non-substituted mi...

The microgrid (MG) is a popular concept to handle the high penetration of distributed energy resources, such as renewable and storage systems, into electric grids. However, integration inverter-interfaced generation units (IIDGs) imposes control protection challenges. Fault identification, classification isolation are major concerns with IIDGs-based active MGs where IIDGs reveal arbitrary imped...

PURPOSE This single-masked randomized clinical trial aimed to evaluate the effectiveness of orthokeratology (ortho-k) for myopic control. METHODS A total of 102 eligible subjects, ranging in age from 6 to 10 years, with myopia between 0.50 and 4.00 diopters (D) and astigmatism not more than 1.25D, were randomly assigned to wear ortho-k lenses or single-vision glasses for a period of 2 years. ...

In this research paper, the performance of an air-cored axial flux permanent magnet synchronous generator is evaluated for low speed, direct drive applications using 3D finite element modeling and experimental tests. The structure of the considered machine consists of double rotor and coreless stator, which results in the absence of core losses, reduction of stator weight and elimination of cog...